Vulnerability · Published Jan 14, 2026 · Assigned by VulnCheck

CVE-2026-22211TinyOS <= 2.1.2 Global Buffer Overflow in printfUART

Medium 5.1

In plain English

A medium-severity out-of-bounds write in TinyOS from TinyOS. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities).

Severity (CVSS 4.0)5.1Medium

Exploit odds (30 days)0.2%top 93.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

TinyOS versions up to and including 2.1.2 contain a global buffer overflow vulnerability in the printfUART formatted output implementation used within the ZigBee / IEEE 802.15.4 networking stack. The implementation formats output into a fixed-size global buffer and concatenates strings for %s format specifiers using strcat() without verifying remaining buffer capacity. When printfUART is invoked with a caller-controlled string longer than the available space, the unbounded sprintf/strcat sequence writes past the end of debugbuf, resulting in global memory corruption. This can cause denial of service, unintended behavior, or information disclosure via corrupted adjacent global state or UART output.

Affected products (as reported)

Vendor	Product	Versions
TinyOS	TinyOS	0 – through 2.1.2

Weakness: CWE-787 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

References

https://seclists.org/fulldisclosure/2026/Jan/14 technical-description, exploit
https://github.com/tinyos/tinyos-main product
https://www.vulncheck.com/advisories/tinyos-global-buffer-overflow-in-printfuart third-party-advisory